UXO Clearance Starting at 1.4 GW UK Offshore Wind Farm Site

July 2, 2024, by Adrijana Buljan

Hughes Subsea, a subsidiary of OEG Renewables, will start disposing of unexploded ordnance (UXO) at the UK 1.4 GW East Anglia Three (EA3) offshore wind farm site on 4 July, according to the latest Notice to Mariners issued by the EA3 project team.

The Glomar Wave vessel at sea, to be used at Beatrice offshore wind farm — Glomar Wave; Image source: Glomar Offshore/Rovco

The UXO identification, investigation and clearance campaign started in March this year after Hughes Subsea signed a contract to carry out the work for the offshore wind project.

After starting UXO identification and investigation, the company confirmed multiple UXOs at or around several wind turbine locations, inter-array connection routes and the offshore substation location.

For the clearance work, which is scheduled to start on 4 July, the company will be using the DP2 vessel Glomar Wave which, after mobilisation, will begin disposing of the confirmed unexploded ordnance (cUXO) by using a work class remotely operated vehicle (ROV) and low-order detonation operations.

The first campaign will focus on clearing seven priority targets located within the wind turbine array site, followed by the remaining cUXOs.

Once all cUXOs have been cleared, the vessel will continue identification operations on the remaining potential unexploded ordnance (pUXO) targets. Any further cUXOs discovered in the upcoming identification period will be disposed of in a second clearance phase.

Besides the wind turbine array site, Hughes Subsea will also carry out the same work along East Anglia Three’s nearshore section of the export cable route, near Bawdsey, starting on 5 July.

For the nearshore UXO investigation and clearance, diving operations will be carried out from the vessel HM Denham to identify potential UXO among 20 targets, followed by disposal or relocation as required.

The UXO identification and clearance work for the 1.4 GW offshore wind farm is expected to be completed by October 2024.

Located 69 kilometres off the coast of Suffolk, England, the East Anglia Three offshore wind farm will comprise 95 Siemens Gamesa 14+ MW wind turbines and is expected to start delivering electricity in 2026.

The project, developed by ScottishPower Renewables, has already started onshore construction and the production of offshore wind turbine components, and is expected to be operational in 2026.